Surgical procedures commonly involve incising or puncturing the skin or other biological tissue. Once a surgical incision is made in the skin, the natural elasticity of this tissue will tend to close the wound. Therefore, it is necessary to retract the edges of the incision to visualize and access underlying structures.
A variety of retractors have been developed for these purposes. Many retractors involve flat plates or tissue gripping structures at the ends of two hinge-connected arms. The edges of the incision are moved apart by inserting the flat plates or tissue gripping structures into the incision and separating the plates or gripping structures by activating the hinge.
One problem with many existing retractors is that they do not provide full protection to the edges of the incision from trauma caused by advancing instrumentation through the incision. Trauma to the edges of the incision decreases the amount of contamination needed to cause a wound infection by compromising the natural ability of cleanly incised biological tissue to resist infection.
Further, many retractors do not protect the edges of an incision from exposure to cancer cells and infective agents during extraction of tissue through the incision. This failure increases the incidence of both cancer in the incision tract and wound infections.
In addition, there has been a trend in recent years towards replacing conventional open surgical procedures with laparoscopic and endoscopic procedures. These minimally invasive procedures require small incisions often having a diameter of less than about five centimeters. Biopsies of the breast and other tissues also frequently require small incisions.
Retraction of the edges of a small laparoscopic incision is often accomplished by placing a canula in the incision. Widening the incision involves replacing the canula with canulae having successively larger cross-sectional areas. This process is time consuming and adds to the expense of the procedure.
Hence, there is a need for a self-retaining retractor that can be used in small incisions, that can adjustably expand the edges of the incisions, and that can protect the edges of an incision from trauma caused by the introduction of instrumentation and during the extraction of tissue. The present invention is an incision retractor suitable for use in small surgical incisions, able to expand the incision to a plurality of cross-sectional areas and designed to overcome the problems inherent in the prior art by increasing the protection provided to the edges of the incision. Thus, the present invention is designed to increase the ease of performing surgical procedures, particularly those utilizing small incisions, and to increase the likelihood of uneventful healing following surgery.